Nogueira Nadir F S, Gonzalez Marcelo S, Gomes José Eugênio, de Souza Wanderley, Garcia Eloi S, Azambuja Patricia, Nohara Lilian L, Almeida Igor C, Zingales Bianca, Colli Walter
Laboratório de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ, Brazil.
Exp Parasitol. 2007 Jun;116(2):120-8. doi: 10.1016/j.exppara.2006.12.014. Epub 2007 Jan 13.
Trypanosoma cruzi epimastigotes adhere in vivo to the luminal surface of their triatomid vector digestive tract by molecular mechanisms, as yet, unknown. Here, we show that the administration of 0.5 microM epimastigote major surface glycoinositolphospholipids (GIPLs) to the infected bloodmeal inhibits up to 90% parasite infection in Rhodnius prolixus. The parasite behavior was investigated in vitro using fragments of the insect midgut. The addition of GIPLs in concentration as low as 50-100 nM impaired 95% the attachment of epimastigotes. Previous treatment of GIPLs with trifluoroacetic acid to remove the terminal beta-galactofuranosyl residues reversed 50% the epimastigote in vitro attachment. The binding sites of purified GIPLs on the luminal surface of the posterior midgut were exposed by immunofluorescence microscopy. These observations indicate that GIPLs are one of the components involved in the adhesion of T. cruzi to the luminal insect midgut surface and possibly one of the determinants of parasite infection in the insect vector.
克氏锥虫前鞭毛体在体内通过尚未明确的分子机制附着于其锥蝽媒介消化道的管腔表面。在此，我们表明，向受感染的血餐中添加0.5微摩尔的前鞭毛体主要表面糖基磷脂酰肌醇（GIPLs）可使长红锥蝽的寄生虫感染率降低多达90%。利用昆虫中肠片段在体外研究了寄生虫的行为。添加低至50 - 100纳摩尔浓度的GIPLs可使前鞭毛体的附着减少95%。用三氟乙酸对GIPLs进行预处理以去除末端β - 半乳糖呋喃糖基残基，可使前鞭毛体的体外附着逆转50%。通过免疫荧光显微镜观察到纯化的GIPLs在后肠管腔表面的结合位点。这些观察结果表明，GIPLs是参与克氏锥虫附着于昆虫中肠管腔表面的成分之一，并且可能是昆虫媒介中寄生虫感染的决定因素之一。
